Al2O3/TiO2 bi-layer films on alummium substrates have been obtained by combining anodising and TiO2 sol-gel deposition. The reflectivity enhancing properties of these Al2O3/TiO2 bi-layer films have been studied in relation to the refractive index and thickness of the Al2O3 and TiO2 single-layers. It is shown that a significant improvement of reflectivity can be achieved by a proper optimisation of the bi-layer elaboration parameters. (c) 2007 Elsevier B.V. All rights reserved.